Shredder structure

ABSTRACT

An improved shredder construction including a revolving shaft and a series of blade assemblies mounted by their associated hubs to the shaft. The individual hubs or hub sections are keyed to the shaft, whereas the respective blade assemblies are pinned to their respective hubs or hub assemblies. In the invention the composite hub structure includes a series of hub sectors, generally two, which are bolted together at opposite sides. Cutter bar bases supporting cutter bars operatively associated with the blades are raised at their underneath dimension such that centrifugal force will cause debris hanging on to the blade assembly, exposed relative to the cutter bases, to be thrown outwardly and downwardly free of the equipment. Accordingly, the cutter bar structure including their bases are relieved such that the blades will be exposed proximate their lowermost peripheral trajectories of travel. Blades are likewise affixed to the lower edges of the cutter bar structure such that should there be any remaining debris clinging to the blade structure, the same will be simply brushed or sheared as the blade returns upwardly, relative to its outer extremity, into the region between adjacent cutter bars. Solely a scissor-shear action is employed at the upper and lower edges of the cutter bars.

United States Patent [1 1 Brewer July 8, 1975 SHREDDER STRUCTURE [75] Inventor: John C. Brewer, Salt Lake City, [57] ABSTRACT Utah An improved shredder construction including a re- I volving shaft and a series of blade assemblies mounted [73] Asslgnee' fi fgzg igf sgfi of Amenca by their associated hubs to the shaft. The individual hubs or hub sections are keyed to the shaft, whereas Filedi 1, 1974 the respective blade assemblies are pinned to their re- [211 App]. 465,898 spective hubs or hub assemblies. In the invention the composite hub structure includes a series of hub sec- Related Applicatiml Data tors, generally two, which are bolted together at oppo- [63] Continuation-in-part of Ser, No, 335,003, 23, site sides. Cutter bar bases supporting cutter bars opl973, Pat. No. 3,840,187. eratively associated with the blades are raised at their underneath dimension such that centrifugal force will [52] U.S. Cl 241/243; 241/292.1 cause debris hanging on to the blade assembly, ex- [51] Int. Cl. B02C 18/06 posed relative to the cutter bases, to be thrown out- [58] Field of Search 241/190, 191, 197, 243, wardly and downwardly free of the equipment. Ac- 24l/292.l, 294, 298, 300 cordingly, the cutter bar structure including their bases are relieved such that the blades will be exposed '56] References Cited proximate their lowermost peripheral trajectories of UNITED STATES P N travel. Blades are likewise affixed to the lower edges 2,956,602 l0/l960 Griinberg 241 243 of the l bar F' that shuld be Loch-'28 9/196, Kitchen km 241,190 X any remaining debris clinging to the blade structure, 2 925 4 9 2 G 'j b 24 90 the same will be simply brushed Ol' sheared as the 329,921 1/1966 He s er 3|, 2 1 190 blade returns upwardly, relative to its outer extremity, 1,708,127 1/1973 Brewer....... 241/19l X into the region between adjacent cutter bars. Solely a {762,655 l0/l973 Brewer 24l/32 scissorhear action is emplgyed at the upper and 'rimary Examiner-Granville Y. Custer, Jr. lssistant Examiner-Howard N. Goldberg lower edges of the cutter bars.

7 Claims, 6 Drawing Figures FiAjTFiTW WJUL 81975 LLl mmmkm SHREDDERS TRUCTURE This is a continuation-impart of the inventors prior application entitled SHREDDED MECHANISM AND IMPROVEMENTS THEREINISer; No. 335,008, filed Feb. 23, 1973, noivisstietl UiSJPaL No. 3,840,187.

The presentinvent iorrrelates to theindustrial shred ders such as .shr'eddets usablein reducing municipal waste, garbage and the like and, more particularly, to a shredder having a series of mutually spaced revolving blades, preferably arranged in a helical pattern about the axis of the revolving shaft associated with the several blade structures. The blade assemblies are transversely pinned to hubs which are made up on the revolving shaft as by positioning keys. Shear pins are used so as to provide a safety feature for the blades. The hubs are uniquely designed so as to provide a tight take-up on the shaft as well as facilitate the slight clearance that might be desired relative to the blade structure such that the same will easily slip about the hub should shear pins become sheared as through overload.

The cutter bar structures are relieved along their lower margins such that as each blade assembly revolves, its tip will protrude downwardly beneath the lower contour of the cutter bar structures. In this way, material clinging to the blade will be freed from the constraining influence of the associated, mutually parallel cutter bar structures so that such material as clings to the blade will be thrown outwardly be a centrifugal force. Should any debris remain, then the same can be cut, or simply scraped from the revolving blades, such as by appropriate blade means as attached to the lower contour of the respective cutter bar structures.

Accordingly, a principal object of the present invention is to provide a new and improved shredder construction.

Afurther object is to provide, in a shredder construction having a series of revolving blades mounted upon a shaft, improved cutter bar structures which are relieved at their lower margins such that revolving blades will proceed downwardly beneath such contour, thereby enabling debris clinging to the blade to be thrown freely. both from the blade and cutter bar structure. i

A further object is to provide blade means attached to the lower contour of cutter bar such that, as the revolving blade assemblies proceed along their travel paths, any debris clinging to the blade past its lowermost point of travel will be cut, sheared or simply scraped from the blade assemblies, thereby preventing re-entrance of the material between adjacent cutter bar structures.

A further object is to provide for an angular scissorshear actionboth above and beneath the cutter bars, and also for an angulation of the lower cutter bar shearing edge portions whereby to effect maximum, vertically dimensioned support of the cutter bars proximate the blade tips travel paths.

The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The present invention, both as to its organization and manner of operation, together with further objects and advantages thereof, may best be understood by reference to the following description, taken in connection with the accompanying drawings in which:

FIG. 1 is a fragmentary top plan of the structure of the present invention in a preferred embodiment and shows two of a series of blade assemblies with their cutter bars.

FIG. 2 is a transverse vertical section taken along the line 2-2 in FIG. 1.

FIG. 3 is an enlarged section taken along the line 3-3 in FIG. 2.

FIG. 4 is an enlarged section taken along the line 4-4 in FIG. 2.

FIG. 5 is an enlarged section taken along the line 55 in FIG. 2.

FIG. 6 is a plan view illustrated in section and taken along the line 66 in FIG. 2.

In FIGS. 1 and 2 a blade assembly 10 includes a pair of blade halves 11 and 12 which may be identical in shape and secured together by bolts B1, B2, and B3, at each of two places respectively. Each of the blade assemblies will likewise include cutter blade segments 13 and 14 which are secured in place by screws 15 passing into drilled and tapped apertures 16. Apertures l7, l8, and 19 may be drilled and tapped, as well as their counterparts as at 21 and 22 by way of example, so that the entire blade assembly may be secured together. The blade assembly is secured about and includes a hub assembly 23. The latter is comprised of plural hub segments 24, in their assembly resembling a thickened washer having an inner peripheral groove 25, see FIGS. 2 and 4. The hub assembly 23 is secured by one or more keys 26 to revolving shaft 27. Shaft 27 is driven by suitable drive means 28 such as a shaft extension via motor 29. The latter may be bolted by bolts 30 to frame structure 31'.

In returning to a consideration of the hub assembly, at 23, it is seen that the hub segments 24 may be designed to be semi-circles, with the two being secured together by a pair of bolts 31 and 32 and also bolt pair 33 and 34. Thus, the hub assembly is pinned to the shaft as shown in FIG. 3 and, in addition, includes one or more shear pins 35, as seen in FIG. 5. Accordingly, in operation the structure as thus described provides a series of blade assemblies as at 10 and 10' in FIG. 1. Phantom line L illustrates, in conjunction with FIG. 1, that these blade assemblies are staggered, in fact, a locus of the points of the cutting edges or cutting segments of the blades will describe a helix about the axis of shaft 27.

In any event, the blade combination is mounted upon the shaft and operates fully to cut or scissor-shear materials that drop into the hopper H as defined by structure 38. Should there be a jamming of the machine, as to particular blade assembly, then that blade assembly may easily revolve about its own hub assembly 23, this with a breaking of shear pin or pins 35 along one of its cutting planes P1 or P2 as seen in FIG. 5. The prior tightening of bolts 31-34 will allow clearance, as desired, to effect cutter blade slippage.

Of special importance in the invention is the provision of upstanding cutter-bar ribs 39 each having cutter bar segments 40. The latter include recessed screws or bolts 41 which affix the blade segments to the cutter bar 39 by means of drilled and tapped apertures 42. A cross structure at 43 may secure various ones of the respective cutter bars 39, see FIG. 1, in place. It is noted that there will be provided, for the concave, contoured portion 44 of each cutter bar 39, a relieved bottom surface 45 of the cutter bar such that the revolving blade will descend therebelow. This is so that any material sticking to the revolving blade assembly of the latter passes through the spaces S, will be thrown out by centrifugal force, as soon as the material reaches area C; further any slight particles or debris as might remain on the plate may be wiped off, cut, and preferably scissorsheared as by the addition of a respective blade segment 47. These are mounted by attachments 48 to drilled and tapped apertures 49 at each of the angulated surfaces 50 of the several cutter bar bases as at 39.

While the axis of shaft 27 is shown above the horizontal cutting plane of the cutter bar structure proximate 40, it will be understood that the axis of such revolving shaft may be disposed at a lower elevation and beneath such cutter bar plane, but only provided the scissorshearing effect and structure exists at 13 and 40 as well as proximate the lower cutting segments 47. By scissorshear is meant that cutting surfaces approach and pass each other in an angular fashion.

Thus, in the operation of the invention the revolving cutting blades cut or shear materials such as the same proceed downwardly to drop through the spaces S between the cutter bar bases and their cutter bar segments. Any materials that chance to stick upon the blade assemblies will be thrown out by centrifugal force once the blade reaches area C. Should any slight debris remain on the blade at this point, then the wiping or cutting blade at 47 will remove or cut the remaining materials.

Structure S includes a side plate 51 as well as central plate 52 mounted thereto by attachments 53. This structure may be utilized by journaling opposite ends of the shaft 27, and for directing the flow of materials downwardly along the arrow D, and so forth. An aperture as at 53' will be provided, of course, to allow passage for the shaft.

What is provided therefore is a new and improved shredder construction of optimum design, especially at that area of the blade assembly which is intended to slip about its hub in the event of the shearing of the shear pin mountings to the hub, this in the event of overload. Another feature is the provision of sufficient clearance underneath the cutter bar structure so as to enable accumulations upon the blade structure to be thrown out by a centrifugal force, with any debris remaining being wiped or sheared off as by wiping or shearing blade 47 in FIG. 2.

While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects, and within the true spirit and scope of the invention.

I claim:

1. A shredder construction including, in combination, a revolving shaft, a series of interspaced cutter blades having respective shearing portions and keyed to said shaft for revolvement therewith about the shaft's axis of revolvement, a series of mutually spaced, fixedly disposed cutter bars having opposite ends, said cutter bars having upper and lower edges and being cooperatively disposed in alignment between and positioned at least in part beneath the said axis of revolvement of said shaft, said cutter blades in their revolvement cyclically extending beneath said cutter bar lower edges, whereby debris as might tend to cling to said cutter blades will tend to be thrown off through centrifugal force, to deter re-entry of such debris upwardly between said cutter bars, said upper and lower edges of said cutter bars having respective shearing portions re spectively disposed cooperatively with said cutter blade shearing portions and positioned for mutual angular disposition with respect to said cutter blade shearing portions, in acute-angle fashion when said cutter blades are coacting with said shearing portions of said cutter bars at times of the proximate shear-crossing of said cutter blade shearing portions with both of said cutter bar shearing portions of each of said cutter bars, to effect an angular, scissor-type shear, whereby to shear any remaining debris as might cling to said cutter blades as the same approaches said re-entry between said cutter bars.

2. Structure according to claim 1 wherein said cutter blades include oppositely extending arms having respective, opposed, shearing edges configured for shearscissor co-action with said shearing portions of said cutter bars.

3. Structure according to claim 1 wherein each of said shearing portions of said cutter blades and also said cutter bars comprise hardened segments fastened to said cutter blades and cutter bars respectively.

4. Structure according to claim 1 wherein said lower edges of said cutter bars are concave, facing downwardly, said ends of said cutter bars being thereby vertically enlarged to provide needed end support. said construction including support structure bolted to said ends.

5. Structure according to claim 1 wherein said shearing portions of said cutter bars proximate said lower edges thereof are mutually aligned and angulated relative to said shearing portions of said upper edges thereof.

6. Structure according to claim 5 wherein said opposite ends of said cutter bars are vertically enlarged and depending relative to said shearing portions of said cutter bar lower edges.

7. Structure according to claim 1 wherein said spaced cutter blades are mutually helically oriented, said shearing portions of said upper and lower edges of said cutter bars being in respective, planar alignment.

t i il l' 

1. A shredder construction including, in combination, a revolving shaft, a series of interspaced cutter blades having respective shearing portions and keyed to said shaft for revolvement therewith about the shaft''s axis of revolvement, a series of mutually spaced, fixedly disposed cutter bars having opposite ends, said cutter bars having upper and lower edges and being cooperatively disposed in alignment between and positioned at least in part beneath the said axis of revolvement of said shaft, said cutter blades in their revolvement cyclically extending beneath said cutter bar lower edges, whereby debris as might tend to cling to said cutter blades will tend to be thrown off through centrifugal force, to deter re-entry of such debris upwardly between said cutter bars, said upper and lower edges of said cutter bars having respective shearing portions respectively disposed cooperatively with said cutter blade shearing portions and positioned for mutual angular disposition with respect to said cutter blade shearing portions, in acute-angle fashion when said cutter blades are coacting with said shearing portions of said cutter bars at times of the proximate shear-crossing of said cutter blade shearing portions with both of said cutter bar shearing portions of each of said cutter bars, to effect an angular, scissor-type shear, whereby to shear any remaining debris as might cling to said cutter blades as the same approaches said re-entry between said cutter bars.
 2. Structure according to claim 1 wherein said cutter blades include oppositely extending arms having respective, opposed, shearing edges configured for shear-scissor co-action with said shearing portions of said cutter bars.
 3. Structure according to claim 1 wherein each of said shearing portions of said cutter blades and also said cutter bars comprise hardened segments fastened to said cutter blades and cutter bars respectively.
 4. Structure according to claim 1 wherein said lower edges of said cutter bars are concave, facing downwardly, said ends of said cutter bars being thereby vertically enlarged to provide needed end support, said construction including support structure bolted to said ends.
 5. Structure according to claim 1 wherein said shearing portions of said cutter bars proximate said lower edges thereof are mutually aligned and angulated relative to said shearing portions of said upper edges thereof.
 6. Structure according to claim 5 wherein said opposite ends of said cutter bars are vertically enlarged and depending relative to said shearing portions of said cutter bar lower edges.
 7. Structure according to claim 1 wherein said spaced cutter blades are mutually helically oriented, said shearing portions of said upper and lower edges of said cutter bars being in respective, planar alignment. 